Piston for fountain pens



Nqv. 21, 1950 B. NILSEN PISTON FOR FOUNTAIN PENS Berni IVi/sen FiledJune 17, 1948 IN V EN TOR.

Patented Nov. 21, 1950 UNITED STATES Arum] orrics PIstroN son FOUNTAINruns Bernt Nilsen, Barranquilla, Colombia Application June 17, 194s,Serial No; 33,497

The present invention relates to certain new and useful improvements inink-filled fountain pens and has more particular reference to a suctiondeveloping piston and convenient, manually actuable, operating means forthe piston.

As the opening statement of the invention implies, many and varied typesof piston structures have been devised by prior patentees and others toproduce suction in a barrel and to thus suck ink, from a bottle or othercontainer, into the storage reservoir of the barrel. The piston isarranged in most adaptations to reciprocate in or out and is operable bya rod or equivalent means to provide the desired degree of suctionnecessary to draw or suck ink into said reservoir. What is more, certainprior art fountain pens, in the category under advisement, utilize screwthreads for imparting motion to the reciprocable piston. In carrying outthe principles of the instant invention, I likewise rely on theprinciple of screwing the piston back and forth in the barrel in amanner to attain the desired ends with requisite certainty andefficiency.

More specifically, novelty is predicated upon an ink storing anddelivering barrel, the bore of the reservoir of said barrel being screwthreaded, the piston being threaded for operation in the statedscrew-threaded bore and said piston being slidably keyed on a rotatableshaft whose rotation is accomplished by a thumb wheel or the like.

Other and more specific objects and advantages of the invention willbecome readily apparent from the following description and theaccompanying illustrative drawings.

In the drawings, wherein like numerals are employed to designate likeparts throughout the views:

Figure l an elevational view, on a small scale, of a completepocket-type fountain pen constructed in accordance with the principlesof the present invention;

1 Claim. (01. 12 -47)" gap l I and is internally screw-threaded toaccommodate external threads on a rubber or equivalent ring-nut I 2. Thering nut is provided with a conical sleeve or bushing l3 which, inpractice, serves to accommodate the cylindrical portion it of the pistonrod. The upper end of the rod in Figure 2 is provided with a flange l5which is swivelled in the nut and is further provided with a milledfinger knob or grip I6 which is normally covered within the cap. Themajor portion of the turntable piston rod is oval in cross section asindicated at IT, and the piston, which is denoted by the numeral 18, hasan oval bore which fits snugly on the rod and which permits the pistonto work back and forth in an obvious manner More specifically, thepiston is in the form of a sleeve which is externally screw-threaded, asat I 9, and said threads screw into the threads 9. The upper end of thepiston is provided with a socketed collar portion '10 which serves totelescopically receive the bushing [3 when the collar portion is backedup against said bushing. The sleeve i3 is of the requisite degree offlexibility and tends to pack into the socket in the collar 2!} when thepiston is at the extreme I upper position. Thus, a substantiallyfluid-type Figure 2 is an enlarged fragmentary sectional andelevatio-nal view on the line 2-2'of Figure 1, looking in the directionof the arrows; and

Figures 3, 4, 5 and 6 are cross sectional views on the lines 3--3, 4-4,5-5 and 6-6, respectively, of Figure 2.

Referring now to the drawings by distinguishing reference numerals, thecustomarily shaped and proportioned barrel is denoted by the numeral 8and this is open at opposite ends and internally screw-threaded, as at9. One end of the barrel is fashioned into a reduced neck portion inwhich is externally screw-threaded to accommodate internal screw threadson a closing seal is had which will prevent the leakage of ink betweenthe piston and piston rod.

Assuming that the reservoir of the barrel is empty, the piston rod isturned by the thumb knob and the piston is screwed or fed forwardly ordownwardly into the barrel. to a desired or predetermined degree. Then,the pen 2! on the writing end of the barrel is dipped into the ink inthe usual way and the piston rod is rotated in an opposite direction todevelop suction in the reservoir between the pen 2i and the piston. Thepiston is progressively fed in the same direction until it comes intoabutting contact with the bushing. The bushing telescopes into thesocket of the collar 20 and when the piston is home, rotation of thepiston rod is stopped. The crowding or packing of the flexible bushinginto the socket in the piston provides the desired ink seal and preventsleakage of ink.

In Figure 1, I have shown a suitable pocket clip 22 and in practice anappropriate closing cap (not shown) may also be provided.

In view of the foregoing description taken in conjunction with theaccompanying drawings, it is believed that a clear understanding of thedevice will be quite apparent to those skilled in this art. A moredetailed description is accordingly deemed unnecessary.

It is to be understood, however, that even ing an opemendedbarrelhaving"a-,.cylindrical bore, the wall of said bore being screw-threaded,a sleeve defining a piston, said sleeve being ex-.

ternally screw-threaded and screwed into the screw threads of said boreand operable back and? forth in the bore, the bore of said sleeve beingoval in cross section, a piston feeding rod having a portion oval incross section extending; through":

the oval bore in said sleeve, said rod being located centrally in thebore of. said barrel, a: screwthreaded bushing screwed into one end ofthe barrel, said: bushing: having an: axial cylin drical; passage, saidrod'i passing: through; and: being I rotatable in saidipassagepthatportionaof the rod" passing through said: cylindrical passage beingcylindricalrzinacross' section, a; pen" niban'di:ink-feeding.;means;mounted" for opera! tion in the other end ofsaid barrel, the end of said rod beyond the normal upper end of saidbarrel being provided with a thumb knob, said barrel terminating in anexternally screw-threaded neck, and a screw cap threaded on said neckand enclosing said thumb knob, the upper end of the portion of thesleeve surrounding said rod being recessed and providing a socket, andthe portion of said bushing surrounding said rod being reducedzandadaptedtto telescope into said recess, whereby to effectaliquid-tight'seal between the bushing and sleeve when latter are inpositive abutting relationship.

BERNT NILSEN.

REFERENCES CITED 'Iher-followingv references are of record in the fileof this patent:

UNITED STATES PATENTS Number- Name Date 1,117,469 Wisemanet al Nov. 17,1914 1,??8332. Gaarder'et a1. Dec. 18, 1923 2,328,973 Goldfisher Sept.7, 1943 2,329,367: Weisenberg Sept. 14, 1943

